Don't Forget!
by Tobias Survival
Summary: Sans backstory, anyone? Gaster and Sans FINALLY managed to build that machine. And when they did, they think that it could save Chara and Asriel. Maybe even bring Monsters and Humans back into harmony. But they discover that sometimes the impossible should stay impossible. Rated M for strong language. Will eventually branch into separate Genocide and pacifist fics from Sans's POV.
1. Chapter 1 - We dit it

The elevator practically crashed into the basement. Again. Sans flew back and banged his head against the wall. Again. They needed to put some frikkin seatbelts in here before he cracked his head open for real.

Sans groaned and rubbed his head as the elevator doors slid open. He hoisted himself off the floor, wobbling his way into the cold, dark, borderline slimey lab. This place never failed to give him the creeps. Even though he spent a good chunk of his life down here, for some reason he almost always shivered upon going down the hallways. There were times that you couldn't even see the end of the hallways. They needed to get some goddamn lights in this place. But for some reason Gaster always liked it this dark. Said it always "Helped him think better" or something like that.

He opened the door to the study room, where he found Gaster hunched over his desk, furiously scribbling on paper.

"... Gaster? What's up?" He asked, looking around the annoyingly dark room. It was a miracle he could write anything down in here. Gaster didn't respond. He squinted aggressively at his writing, his glasses slightly crooked from forgetting to straighten them.

"Uh… Whatcha call me here for?" Sans asked as he walked the rest of the way through the door. Gaster finished his last number on the paper, looking it over it again and again to make sure everything was correct.

"Sans… I think I did it." He whispered. "I think I found a way."

"Uh… Okay… I'm not one to criticize a prank, but I seriously just walked all the way over here from Snowden and Grillbyz was-"

"I'm serious, Sans." He interrupted, handing him the paper.

"Uh… Are you sure? I mean… You've been working on this since before… Well… Me." Sans glance over the paper, scanning through the equations. "I mean, there's no way-"

Sans stopped in his tracks, sockets widening as he read more closely.

"Holy… Holy shit. Are you serious?! Are you… No way. No _fucking_ way."

"Sans… I've done it." He said, putting a hand to his head and smiling. "I've done it. I can't believe it. It's been so long..."

"Hey, Hotshot. I helped with at _least_ a third of it. Gimme at least a little credit."

"Of course, forgive me. _We_ did it, Sans. We did it."

"Nah, I was just fuckin with ya. I did next to nothin." Sans looked over the paper once more, this time, it must have fully hit him. His hand started shaking, blue dripping from his sockets, almost dripping onto the paper.

"Have… Have you told Alphys? Asgore?" He sniffed, a half grin forming on his face.

"Not yet. I wanted to let you know first." Gaster said proudly.

"... God… We did it. I can't believe this." Sans whispered, wiping his face and handing the paper back to him. "Can I… Can I tell Papy-"

"Wait a little while. We still need to test to see if it works." Gaster said, resting a hand on Sans's shoulder. "But in the meantime, think about what we've accomplished, Sans. This… This will change everything. This will change Monstrosity… This will change Humanity… This… This will change the _world_ Sans."

"I… I know, Gasty. I know… I'm… I'm just so happy knowing that all of that work… Every second of it… It wasn't all for nothing. I just…" Sans put his face in his hands, his shoulders shaking. "We've been working on this for as long as I can remember… God, we did it. We finally did it."

Suddenly, Gaster kneeled down and embraced Sans. He made muffled sound of surprise against his lab coat in surprise. He eventually returned the hug, feeling warmth down to his marrow.

"Sans, we could make it so that Monsters and Humans can be at peace again... We can make it so that the war never happened."

"I know… I know Dad."

* * *

"SANS! YOU'RE ACTING MUCH HAPPIER THAN USUAL TODAY! THAT'S FANTASTIC!"

Sans heard Papyrus shout at from the other room as he hummed while he stirred an egg mixture in a bowl.

"I guess so, bro. I guess so." He said, shaking salt and pepper into the mix.

"WHY, YOU'RE COOKING AND EVERYTHING! INCREDIBLE! YOU MUST HAVE FIGURED OUT WHAT I WAS GOING TO ANNOUNCE TO YOU AND GASTER TODAY!"

Sans grinned, putting down the whisk and turning away from the quiche he was making.

"Yeah? What's that, bro?" Sans asked, finding Papyrus standing proudly before him.

"FAKING THAT YOU DON'T KNOW WHAT I'M TALKING ABOUT SO THAT YOU'LL MAKE ME FEEL BETTER, EH? FEAR NOT! FOR I AM NOT OFFENDED BY YOUR ACCIDENTAL REALIZATION! IN FACT, JUST TO PROVE HOW NOT OFFENDED I AM, I SHALL PLAY ALONG AND TELL YOU ANYWAY!"

Papyrus cleared his throat and stood tall, towering over Sans.

"I, THE GREAT PAPYRUS, HAVE DECIDED THAT I WANT TO JOIN THE ROYAL GUARD! I WILL PROTECT THE ENTIRE UNDERGROUND WITH MY SKILL AND MIGHT! I WILL BECOME KNOWN AS THE MOST BRAVEST, THE MOST MIGHTY, AND THE MOST CHARISMATIC KNIGHT IN THE ENTIRE UNDERGROUND! NO, THE WHOLE WORLD I SAY!"

Sans's smile shrunk. He almost let it be smacked off of his face, but he stopped himself just in time.

"HMM? WHAT'S WRONG, BROTHER? YOU SEEM UPSET ABOUT SOMETHING."

Sans shook his head, snapping himself out of it.

"What? 'Course not, dude. I'm just-"

IN AWE, ARE YOU? SURPRISED THAT I WOULD PUT MY GREATNESS ON THE LINE? ONCE AGAIN, FEAR NOT! I WILL SURVIVE ANYTHING THAT ANYONE THROWS AT ME! I WILL SIMPLY LOOK AT ANYONE THAT GETS IN MY WAY, AND THEY WILL TREMBLE IN FEAR BEFORE ME! THEY WILL FORGET THAT THEY WERE SUPPOSED TO FIGHT ME, AND WILL RUN COWERING IN FEAR, GRANTING ME VICTORIOUS!"

Papyrus, kneeled down next to Sans, putting an arm over his bended knee.

"DO NOT WORRY, BROTHER! FOR NO HARM SHALL COME TO ME! I ASSURE YOU!"

Sans forced himself to smile, not making eye contact.

"Thanks, Papyrus. I feel a lot better knowing that. Now, I gotta get back to makin that… Uh… Thing. 'Kay? You work on that."

"BUT OF COURSE!" Papyrus exclaimed. "I SHALL BE IN CONTACT WITH THE CAPTAIN, UNDYNE, AS SOON AS POSSIBLE!"

"Alright, but not before dinner, okay? I'm workin real hard on this and I don't want it all to go to waste." Sans said, going back into the kitchen.

"UGH, FINE. BUT MAKE IT QUICK! I NEED TO GO PRACTICE MY ACCEPTANCE SPEECH!" He said, dashing up the stairs and into his room.

Sans let his face drop.

He didn't have the heart to tell him that the Royal Guard would be obsolete soon.


	2. Chapter 2 - A favor

"SANS! CAN YOU GET THE DOOR? I'M STILL WORKING ON MY BATTLE BODY."

Sans groaned as he rolled to the other side of his bed and covered his head with a pillow. He had a long day of research with Gaster today. He may have been have been glad that they had finally figured it out, but that doesn't mean he still hates the work. And suffice to say, he wasn't looking forward to it. He lifted his pillow slightly to look at the clock. 9 AM. Had Papyrus been working on his costume all night? Jesus, at this rate he'll actually get sick if he doesn't sleep.

He slowly shrugged his blankets off, making excuses for himself in his head about why he should take his time. And by take his time he meant never get all the way out of bed. But eventually he slowly sat up in his bed, putting his face in his hand and rubbing his forehead.

"SANS, PLEASE HURRY. THEY'VE BEEN WAITING FOR QUITE SOME TIME NOW."

He dragged his hand down his face, dreading getting out of the bed. But he somehow put on his slippers he kept at the side of his bed, and slowly stood up.

Well, one miracle had already happened that day. And he didn't normally wake up until at _least_ three hours from now.

He dragged his feet across the room, picking up dirty laundry that was laying on the floor around his legs. He fumbled to get a grip on the doorknob, almost purposely not using his thumb.

The door finally clicked open, and he pushed it forward with the effort of next to nothing. He squinted at the sudden brightness of the house. Pap had even forgot to turn out the lights last night. He hoped Gaster had made enough last night to cover what electricity bill Pap had made within the past week alone.

Suddenly, there was a knock at the front door. It snapped him out of his daze and put him on edge. It was way too professional sounding. The most uptight knock they had ever received was whenever they had a package delivered. And even that was just a half-assed placement of knuckles.

He cautiously made his way down the stairs, not taking his eyes off the door. It somehow looked cold. And not just because they lived in a tundra.

There was another knock when he put his hand on the doorknob. It set him off even worse. Why was he so put off by a knock? Someone was literally just asking for entry. No one that wanted to hurt anybody would _ask_ to come in.

Right?

He braced himself anyway. His fingertips sparking blue as he swung open the door.

It was the Dogi from the royal guard. Dogamy and Dogaressa, the soon to be married couple. Second only to the King and Queen for being the cheesiest couple in the underground. He'd chatted with them a few times at Grillby's. They were pretty chill. He stopped himself from breathing a sigh of relief at the sight of them. Until he noticed that they both had their hoods pulled over their heads, which were hanging low. Their tails were tucked between their legs.

"Uh… Hey guys. What's up?" He asked, trying his best to sound casual.

"We regret to inform you…" Dogamy mumbled, trailing off his sentence.

"(We were commanded to tell you...)" Dogaressa choked out, tears lining her voice.

They were both silent for a good ten seconds.

"Guys, what happened?" Sans asked, upon hearing Dogaressa whine in despair. Dogamy suddenly stood up straight and pounded his axe handle against the ground in a regal manner.

"... The… The King and Queen have lost the life of their child." Dogamy said, his voice faltering slightly. "And… And their foster child."

"... What?"

Dogaressa's shoulders shook, and Dogamy put a hand on her shoulder. She seemed to gain a slight amount of strength.

"(The humans… Are responsible.)" She sniffed. (Therefore… The King h-has declared that every h-human that comes here m-must die.)"

"Once the king has enough human souls... He… He will shatter the barrier and free us all." Dogamy said, trying to sound happy about it.

Sans stood in the open door, stunned. Snow was drifting carelessly into the house from the wind. Dogamy's hand formed into a fist and Dogaressa's whines became more audible.

"With Gaster being the head royal scientist, you and your brother have been chosen by the King to act as sentries along with us." Dogamy declared. "We will start in three days. Prepare until then."

They bowed quickly in unison and scampered away. Sans stood in the open doorway for a little while longer, hearing the wails of despair coming from Snowden of everyone who had just found out the news. He blinked a couple of times before slowly closing the door, falling back onto it when it shut.

"SANS, WHO WAS IT?" Papyrus asked as he strode out of his room. "WAS IT THE KING PERSONALLY ACCEPTING ME INTO THE ROYAL GUARD?"

"... Papyrus…"

"WOWIE! I CAN'T BELIEVE IT'S ALREADY HAPPENING! I HAVEN'T EVEN TALKED TO UNDYNE YET AND I'VE ALREADY BEEN ACCEPTED! I'LL BE RISING IN THE RANKS IN NO TIME!"

"Papyrus, we might need a rain check on that."

"WHAT?!" Papyrus shouted from over the banister, followed by him rushing down the stairs. "WHAT ON EARTH ARE YOU TALKING ABOUT, BROTHER?! WAS IT NOT HIM AT THE DOOR?"

"No… No it wasn't."

"WHO WAS IT THEN?!"

Sans finally looked up at Papyrus, who's expression shifted upon seeing Sans's face.

"Brother… What's wrong?" Papyrus asked, in one of the calmest tones he'd ever heard him speak.

Sans took a deep breath.

"We just got a new job, buddy."

* * *

Sans gazed around the throne room. It could hardly be called a room, it was outside. The sun shone down on the single throne in the center. The other throne had been moved to the back corner, two monsters were busy covering it in a white sheet. He squinted at them. Wasn't that the queen's throne? What happened? Gaster stood beside him, waiting patiently for King Asgore to return. He seemed unphased by all of this. Then again, he was hardly ever phased by anything.

Just then, Asgore appeared in the doorway with a tray of two steaming cups of tea.

"Thank you two for coming on such short notice." He said as he approached them, proceeding to hand each of them a cup.

"It's no trouble at all, You're Highness" Gaster said, not breaking his eye contact with Asgore as he took the cup in his hands.

"Gaster, please, we've been over this. Call me 'Asgore'." He said, handing Sans a cup.

"Sorry Alphys couldn't make it." Sans said as he accepted the cup, feeling the heat twinge against his fingers. "She's... Uh... Not taking this whole thing too well. So we decided to let her have a break." He awkwardly tapped the side of the cup, making it clink and ring in his ears. "Do, uh, you have anything you need us to do?"

Asgore sighed deeply, putting the tray on his throne.

"Marki and Marko, thank you." He said gently, turning to the monsters who had just finished putting the sheet on the throne. "You've been a big help. You can go now. Please come and visit me later at my house."

They both bowed and shot out of the room. Leaving Sans, Gaster, Asgore, and the birds behind.

Asgore stood at the foot of his throne and hung his head.

"How close are you to finishing the machine?" He asked quietly.

"Not very." Sans said, absentmindedly swishing the tea around in the teacup. "Whyda ask?" He immediately stopped swishing, realizing the answer to his own question as soon as he asked it.

Asgore's shoulders shook slightly. The internal battle he was having with himself was becoming visible.

Gaster's eyes widened.

"Your Highness… You're not thinking…"

"My wife ran away." He whispered. "She left last night."

The room rang with an almost painful silence. Sans stopped himself from letting his jaw drop. There's no way. The Queen would never do anything like that. She loved the King more than he'd seen anyone love anyone. Tons of people found it disgusting how much they loved each other. And she just up and left? No way. No fucking way.

"No one's been able to find her." Asgore said as he put his hand to his head. "We've looked everywhere we possibly could. She's disappeared."

"I… I apologize, Your High- Asgore." Gaster corrected himself. "That is truly upsetting. But I think you should think this over before-"

"I didn't want to come to this." Asgore interrupted. "I really didn't. It took everything I had to not ask when…" He stopped, his breath shaking. Sans thought he might have seen tears in his eyes. "But I can't take this. I can't take this much pain. I'm begging you. Finish your machine as soon as you possibly can, and fix all of this."

"We've only just discovered that it's even possible." Sans explained "We're not really sure how to execute it. It could take literal years."

"Please."

There was a crack in Asgore's voice that made Sans cringe.

"Asgore… I promise we will work as hard as we possibly can to get it done." Gaster said, placing his teacup on the tray.

"Thank you." Asgore sighed. "Thank you."

Sans looked up at Gaster and nodded his head to the side, indicating they should talk to each other in private. Gaster nodded back and they took a few steps forward and turned their backs to Asgore.

"Uh… Gasty…" Sans whispered to him. "This isn't going to happen any time soon. Why're you saying this…?"

Gaster squinted at the ground, making the face he makes when he's thinking really hard. He had always been good at analyzing every possible option within a short time span. Sans could practically see every scenario flashing through his eyes like a TV screen. After about thirty seconds of him being unsettlingly still, he turned back around and approached Asgore. Sans followed suit.

"How long do you think it'll take?" Asgore asked, wiping the now visible tears from his face.

"Uhh…" Sans nervously took a sip of the golden yellow liquid.

"... Will you settle for three months?" Gaster asked nonchalantly.

Sans sputtered and choked on his tea, trying to keep his cough down. It ended up just sounding like he was getting punched in the stomach repeatedly.

"... Can you really do it in that short a time?" Asgore asked in amazement, slowly lowering his hand from his face.

Sans flicked his eyes between Gaster and Asgore. Was he serious? Was he actually serious? Or was he learning to have a sense of humor all of a sudden? Either one was impossible. How the everliving hell were they supposed to finish it in _three months_?!

"I'm sure of it." Gaster stated. Sans gulped down his tea in one big chug, letting it burn his throat.

"Thank you. Thank you so much." Asgore repeated. "I'll be sure to pay you in full, for the expenses of the parts you need and plenty for your labor. Sans, you can retire from Sentry duty temporarily while you work on this with Gaster."

"Thanks, dude." Sans said, staring blankly into his empty teacup.

He wished the universe could give him a break for just a minute


	3. Chapter 3 - Working

Dear God please save me.

It was a phrase that went through Sans's head almost constantly during the first month. He had never worked so hard in his life. Which... Wasn't saying much. But there's no way that nobody else would find this exhausting, right? Every day he woke up at 5 AM, walked all the way to the lab, crashed the elevator, hit his head in almost the exact same spot every time, sat down at his desk, and worked for hours. For _hours_ he stared at paper, writing calculations and estimating probabilities. He was barely able to eat three meals a day. He would stay up until 1 or 2 in the morning, then head straight home and sleep until he had to get up again. It was a cycle that seemed to scratch away at the inside of his head slowly, indefinitely.

And while all of that was painful enough, here's the kicker. Almost every single day, he had to throw away everything he had worked on. Literal hours of extremely strenuous work was thrown down the drain almost constantly.

And to be blunt, it made it hard to give it his all.

Gaster seemed to not mind at all. In fact, he almost seemed to enjoy it, the nutjob. He thought he might have even seen him crack a smile once when he threw something away.

"It just means I've narrowed down the answer. Even if it was just a little bit, the truth is coming ever closer." He said, as if it were the most obvious thing in the world.

Sans couldn't give less of a crap. He just wanted to figure it out and have it be over with so that he could finally sleep again.

When he started working, he wouldn't see Papyrus for more than a couple of minutes at a time. And when he did, Papyrus seemed to express concern for him.

"BROTHER, YOU DON'T LOOK SO GOOD. ARE YOU ALRIGHT?"

"Yeah bro, I'm fine. Why'da ask?" He mumbled, slurring his words so badly it ended up just being one word.

"YOU'VE BEEN WORKING ALMOST NON-STOP FOR TWO WEEKS NOW, AND IT SEEMS THAT YOUR PHYSICAL HEALTH IS DRAINING RATHER QUICKLY." Papyrus proclaimed, his hands on his hips and squinting at Sans. "YOU'VE BEEN STARING AT YOUR BOWL OF CEREAL FOR THE PAST FIVE MINUTES WITHOUT EVEN BLINKING."

"I'm just… Waitin' for it to get soggy." Sans said, barely opening his mouth. Truth be told, it turned soggy two minutes ago. He was really just trying to gain the mental strength to go to the lab. It wasn't working.

Alphys had come in to help a couple of times, but she could never do much. She was still finishing up school, and physics wasn't exactly her strongsuit. At first, she came often. Feeling guilty for not contributing to anything.

"No, no, Alphys. We've got it under control." Gaster assured her. "You need to focus on school for now. However, We will need your help soon, and we will call you when that happens."

"A-are you sure?" She asked nervously, glancing behind Gaster to find Sans, sprawled out and face down on his desk. He slowly crumpled up a piece of paper in his shaking hand, and lifted his head up to look at Alphys. She jumped back at his expression. Which was basically a " _dear God please help me please for the love of all that is holy put me out of my fucking misery I haven't slept for more than four hours at a time for over a month and every waking moment feels like nails on a chalkboard I beg of you to end my suffering_ " Look.

"Yes, I'm sure." Gaster confirmed. Sans slammed his head back on his desk, making a painful sounding _thunk_.

Alphys's eyes widened in fear as she gulped.

"O-Okay." She whispered. "I'll check up on you two l-later."

She came back five minutes later to slip Sans a carton of ice cream. He made a mental note to watch that Kissy show with her after this was all over.

It took almost two months in it of itself to even figure out how they should even build it. It didn't have to be fancy, it didn't have to be big, it just needed to work. So why was it so frikkin hard to figure out how to build a hunk of metal?

The day they finally figured it out had been a particularly bad day for Sans. He hadn't slept at all the night before, and he hadn't really eaten that morning. He could barely even answer what two plus two was that day, let alone do Astrophysics. He sat at his desk in the lab, trying to stop himself from nodding off. But it happened anyway. He was drooling on weeks worth of research within five minutes of sitting down. Gaster's voice was what woke him up.

"Sans."

"What?!" He shot up, a piece of paper sticking to his face with him. He quickly pulled it off and threw it on the desk, propping himself up with an elbow, placing his head in his hand and trying to act casual.

"Please call Alphys. I believe I've just found a way to build this."

"Woah, wait, seriously?!" Sans asked as he bolted up from his desk, running to Gaster's side. He nodded, handing Sans a few papers. Sans looked them over quickly before flopping over Gaster's desk in relief.

"Thank. _God_." he exasperated, letting himself fall to the floor.

"I think I'm gonna cry. Am I crying? I'm probably crying, aren't I?" Sans drabbled, rolling over on his side and curling up. "If I ever work another day in my life, please shoot me. Because that's not actually me. It's someone pretending to be me and putting my name to shame by charading me as some hard workin' freak. You know who that's not? Me. I don't work anymore. It's not me. Let me stress: I'm never working again."

Gaster smiled gently while Sans ranted, picking him up from off the floor when he was done and placing him on his feet.

"You can rest today, but you still need to participate in life!" He said, brushing off Sans's shirt as he kneeled next to him. "What would Papyrus do without you? He probably wouldn't be able to find his shoes without you!"

"Aw, c'mon, Papyrus can find his stuff just fine." Sans said, brushing Gaster's hands off of him. "You underestimate him, ya know."

"Still, I couldn't have gotten _nearly_ this far without you, Sans." Gaster affirmed.

"Nah. I do next to nothin'." Sans shrugged, letting himself crack a small smile. "You're the real genius here."

"At least half of this work was yours, Sans. Be proud of yourself." Gaster said, taking him by the shoulders. "You deserve it."

That sentence hit Sans more than it should have. He… Deserved it? The thought never even crossed his mind.

"... Uh… Thanks, Gasty." Sans said quietly. "But uh… _Geez_ I'm hungry. Can I go eat something now?"

"Of course. Just don't forget to contact Alphys. I need her to help with the final design and actually building it."

"Sure thing, hotshot." Sans said, saluting him with two fingers.

* * *

Alphys seemed glad to finally be able to help in some way. She loved to draw and design things, so this project seemed to excite her.

"Geez. You guys really did work hard on this." She commented, looking through the notebook they had put together of all their notes.

"So, can you do it?" Gaster asked politely.

"Oh, yeah. Definitely." She nodded. "Do we have all the materials we need?"

"Yeah. Fluffershnups said he'll provide everything he can." Sans yawned. "We can also probably find stuff in the dump if we need to." Alphys's eyes seemed to light up at the mention of the dump.

"Sans! Don't disrespect the King with such names!" Gaster sighed, putting a hand to his forehead.

"Why not?" Sans shrugged. "I called him that one time and he laughed so hard I think he pulled a muscle." Gaster sighed again and shook his head before turning back to Alphys.

"When can you start on the blueprints?" He asked her.

"Wha-? Oh, uh, r-right now! If you want." She mumbled nervously.

"If you're sure, then you're more than welcome to start." Gaster said, gesturing to their research space. She nodded quickly and scampered to quickly gather supplies.

"And Sans…" Gaster said as he turned to him. "You may rest from research until Alphys and I have finished the blueprints. But when we're done, I expect you to perform tests with me."

"So I get like… A break that's like a month long?! Holy shit. Aye aye, sir!" Sans said, almost halfway out the door.

"Don't forget, you still have sentry duties!" Gaster called after him, making Sans stop in his tracks and cringe. Oh yeah. That.

Well, it can't be any harder than this was, can it?

* * *

Turns out, the only thing he had to do was just sit at a sentry station. That's it. He just had to sit at a sentry station that was right outside of the Ruins, and wait to see if any humans came through. Which they never did. Because the door _never fucking opened._

Well, damn, if he didn't hit the jackpot.

Papyrus, however, took his job _very_ seriously. The King had instructed him to make puzzles. Apparently to trap any humans that passed by or whatever. And sure enough, pretty soon Pap wouldn't talk about anything except puzzles.

"BROTHER, HAVE YOU MADE ANY PUZZLES YET TODAY?" Papyrus asked him. Sans leaned back farther in his chair, balancing precariously with his feet resting on the sentry station.

"Nah." Sans said, picking his teeth with the tip of his finger.

"BUT WHAT IF A HUMAN COMES THROUGH HERE?!" Papyrus yelled, gesturing to the area around them. "THEY COULD EASILY WALK RIGHT PAST YOU IF YOU'RE NOT PAYING ATTENTION."

"Has a human ever actually passed through here?" Sans asked, stretching and putting his arms behind his head. Papyrus glared at him and gritted his teeth, struggling to find a response. Sans felt a smirk crawl across his face.

"I rest my case." Sans said, closing his eyes.

"BUT SANS, I MUST PROVE TO THE CAPTAIN OF THE ROYAL GUARD THAT I AM INDEED, A HARDWORKING INDIVIDUAL! THAT I WILL OBEY THE GUARD'S COMMAND, AND THAT I WILL BE A TRULY VALIANT ADDITION TO THE ROYAL GUARD!"

"You know, you could just try to go talk to her." Sans suggested. "She lives in Waterfall."

Papyrus froze, his face blanking out as if he had an epiphany. He stared at Sans, his jaw gaping open, before suddenly jumping into action.

"OH MY GOD! SANS, FOR ONCE IN YOUR LIFE, YOU'RE RIGHT! AS SOON AS I'M DONE WITH THESE PUZZLES, I'LL GO ASK HER!" He said, running off.

"Dude, it's already pretty late. You'd just wake her up." Sans called after him. But Papyrus had already disappeared into the forest. Sans hummed, returning to his reclined position.

* * *

It had been a month since they had figured out how to build the machine. Sans was thoroughly enjoying his job of doing pretty much nothing all day. And while it was exactly what he wanted, he still didn't get to see Papyrus very often because he was so busy making puzzles all the time. So he was alone most of the day. Every once in a while, a monster might have walked past him and said hello. That was the most action he'd get all day. So he mostly just napped when he could.

But if he was being honest with himself, it was kinda boring.

So he decided to entertain himself by practicing some jokes. He had been thinking up some pretty great ones lately, and wanted to find the perfect way to execute them to Papyrus. Because if he got it just right, Papyrus would actually throw something.

He was actually about to start using a tree stump as a practice dummy, when he had the realization that he was literally sitting next to a giant door all day, so why not?

He shuffled up to the door, cracked his knuckles, and knocked.

"Knock knock." He rapped.

"... Who's there?" Came a soft voice from behind the door.

Sans froze, caught completely off guard. Did… Did someone just… Talk?

"Uhh… Dishes…?" He said, hoping he had just imagined it or something.

"Dishes who?" She asked.

Whelp. There's someone behind there alright. Unless of course he was hallucinating. Which was a real possibility. He still hadn't fully recovered from the neverending nightmare that was that stupid machine. Might as well play along with it and enjoy himself.

"Dishes a very bad joke." He said, waiting to see how he was going to hallucinate her groan of annoyance.

He was surprised when he heard laughter. Like, choking on your own spit laughter. Okay, there's no _way_ that this was a hallucination. He wouldn't have even _begin_ to think that it was going to make her laugh. She actually thought he was funny?

Who the hell was this lady? How did she get into the Ruins? How long has she been there?

And, most puzzling of all, _how_ was she laughing at his joke?

Sans grinned, suddenly finding himself excited to try more jokes.

"Knock knock." He tapped.

"W-who's there?" She choked out through her laughter.

"Interrupting cow."

"Interrupting cow-"

"MOO."

She burst into fits of hysterical laughter, making a thunk that sounded like falling back against the door.

"Yo, you okay?" He asked, putting his ear to the door to listen.

"Ye-yes. I'm fine, thank you." She said, sighing.

"Good, cus I got plenty more where that came from." He bragged.

He continued to knock out jokes to her, and each time she laughed just as hard as the last. No matter how stupid he made them, she absolutely loved it. One time he even tried to make it so that it was impossible to laugh at, but she laughed anyway.

He had to admit, he could get used to this.

He brought his hand to the door to knock once more, but suddenly there came a knock from the other side of the door.

"Knock knock." She said quietly.

He brought his hand down. No way. Was she…?

"... Who's there?" He asked cautiously.

"Old lady." She said, already half-laughing.

"Old lady who?"

"Oh! I did not know you could Yodel!" She said, immediately bursting into giggles. He couldn't stop himself from laughing. Did he seriously just find someone this awesome? She rivaled Papyrus for how cool she was. She laughed at his bad jokes, and she _made_ bad jokes.

"SANS!" He heard Papyrus call from the forest.

"Hold up, I'll be right back." Sans said, recovering from his own laughter. He walked to where he heard Papyrus coming from and found him running from the direction of Snowden.

"SANS! THERE YOU ARE!" He said, slowing down when he spotted Sans. "GASTER TOLD ME TO COME AND GET YOU."

"Huh? Why?" Sans asked, his laughter leaving him.

"HE JUST SAID THAT HE WANTED TO TALK TO YOU IN THE LAB." Papyrus proclaimed, trying to hide the fact that he was out of breath from running so far.

"Uh, okay. Be right there. Just gimme a sec." He said, running back to the door.

He made his way back, wondering what Gaster could possibly want with him in the lab. Did they do something wrong? They couldn't have possibly finished making it already… Right?

"Uh… Listen… I gotta go." Sans said as he approached the door.

"Oh… Of course." She said, disappointment tinging her voice. "I should be going to."

He heard shuffling behind the door, presumably her standing up.

"Uh, wait!" He called, reaching for the door.

"Yes?" The voice asked politely. He cringed. What was he doing?

"Uh… Did you… Uh… Can we do this again?" Sans asked, rubbing the back of his head. Do what again?! Tell lame jokes through a door without even seeing each other? What was coming over him?

"Yes! Of course! I enjoyed myself." She said, excited. "Did you want to meet here same time tomorrow?"

"Uh… Yeah. Sure." He said, surprised at her reply. Did she have as good a time as he had? Huh. Maybe he wasn't going insane after all.

"SANS, WHAT ARE YOU DOING OVER THERE?!" Papyrus called out to him. "GASTER SAID TO HURRY AND THAT IT WAS URGENT."

"Comin' bro!" He called back before turning back to the door. "Uh… See you later, I guess."

"Yes! I look forward to it!" She proclaimed, footsteps following suit.

Why was he so excited to tell dumb jokes to a lady who's name he didn't even know? All he knew was that there was this stupid grin on his face that he couldn't wipe off, and that he didn't really want to wipe off.

"SANS, HURRY UP!" Papyrus bellowed as he took his time coming back.

"Sorry, I'm comin." He mumbled. Papyrus probably couldn't even hear him.

"I BELIEVE HE SAID SOMETHING ABOUT A MACHINE OF SOME KIND?" Pap said as Sans approached him. The smile was finally smacked off of his face.

"Woah, wait, hang on, what? What happened? What'd he say?" Sans said as he quickly ran up to him.

"NOTHING BUT 'PLEASE TELL SANS THAT I NEED HIM TO LOOK AT THE MACHINE WITH ME.' DOES THAT MEAN ANYTHING SPECIAL?" Papyrus squinted at him. "WHAT'S WRONG, SANS?"

"Nothin'… I-I gotta go. Sorry, bro." Sans said, already headed to Hotland.

"SANS, PLEASE BE CAREFUL." Papyrus called out to him.

"Got it!" He called back, hoping to God that they didn't fuck it up.


	4. Chapter 4 - Testing

"Gasty?! What's wrong?!" Sans tried (and failed) to ask calmly as he swung open the lab door, making Alphys jump. Gaster turned to Sans, looking confused.

"What are you talking about? Nothing's wrong." Gaster assured. "In fact, I only have good news."

Sans took a second to absorb what he said before deflating, falling against the wall and sighing in relief.

"Jesus, I just had a heart attack." He grumbled, dragging his hand across his face. "Why does Papyrus make everything sound like a national emergency?"

"Ah… Uh… W-we…" Alphys stuttered.

"We've finished building the machine, Sans." Gaster finished for her.

"What?! Already!?" Sans stood up straight, looking between them both to check if they were serious. Alphys was nervously biting her claws behind Gaster, who was in his usual state of his hands behind his back, standing tall and confidently.

"Yes. Alphys is immensely more talented than I had originally thought." Gaster said, forming a small smile of approval. "We should have let her help us earlier. We would have finished much sooner!" She blushed heavily and hid her face in a textbook that was upside down. Sans felt his face twitch.

"... Are… Are you serious." He mumbled. "She probably could have cut our time in half if you had let her." Alphys squeaked in embarrassment behind her textbook.

"But she was still in school, Sans." Gaster said as he placed a hand on Sans's head. "It was also a very valuable learning experience for you. You were taught a lesson about responsibility and hard work."

"Oh, I learned a lesson alright." He mumbled under his breath as Gaster returned to his desk. He thought he might have heard Alphys whisper "Sorry".

"I called you here so that we can perform tests." Gaster announced as he gathered papers. "Are you ready?"

"Uh… I guess? Where is it?"

"This way." Gaster gestured as he walked towards the door. Sans gave Alphys a "What the fuck is going on" look as she lowered her textbook. She nodded towards Gaster, indicating to follow him. He sighed, turning around and shuffling in the direction of Gaster was headed.

Gaster stopped just before the door and took a hoodie from the coat hanger that Sans had never seen before. It was blue, fuzzy and way too small for Gaster. Before Sans could ask about it, Gaster turned back around and handed it to Sans.

"Here, take this." He asserted.

"Uh… Thanks, boss." Sans said as he took it. "But, what's this for?"

"I know you don't really feel much in the sense of pain and temperature." Gaster said as he put his hands behind his back. "But… I'm still concerned about you getting hurt. This is going to be extremely dangerous, and you could easily-"

"C'mon, Doc." Sans said as he put it on. "You don't have to worry about me. You think I'm going to forget the _literal years_ of training you put me through? The powers that _you_ gave me?"

Yeah, he was being passive aggressive. But he kinda deserved to. Do you know how _fucking hard_ it is to learn telekinesis? To summon blasters? Literal years. Granted, Gaster gave him the powers when he created him. Although it was almost easy to do now, learning how to use them was almost fucking impossible. Papyrus, who had started learning three years ago, could barely even do basic telekinesis; let alone blasters.

When the hoodie slipped onto his shoulders, he was surprised at how comfortable it was. It fit his shape perfectly. Too perfectly.

"Did… You make this?" Sans asked, putting his hands in the pockets.

"... Yes." Gaster said. "I felt… Guilty. Guilty because of how much stress I put you through in past months."

"Wow." Sans said. He found himself suddenly feeling bad about his douche comment. "This Is awesome. Thanks, dude."

"You're welcome, Sans." Gaster nodded. "Now, come. We've work to do."

* * *

Well, it wasn't pretty. That much was true. It was basically the size of a small elevator. With no paint job, and mechanical wires sticking out everywhere, it looked like something the Terminator shit out. But hey, it wasn't supposed to look good. It was just supposed to work, right?

But the inside. Holy shit. Imagine your stereotypical sci-fi machine, with all the glowy buttons completely covering the walls and the ceiling and levers sticking out everywhere, you'd think that it was a movie prop.

Gaster showed him what each group of buttons were. Alphys had designed them to be clustered together based on coordinates, spatial alteratiors, and time alteratiors. Each lever activated a different part of the machine. This one started the motor, this one activated the spatial manipulator, and so on. It looked like a lot, but Alphys had designed it to be as efficient as possible. It was actually pretty easy to figure out. He had to give her credit, she thought of all of this in only a month? She really _could_ have helped them out.

"Now, we're only going to be testing with small inanimate objects today." Gaster said as he pulled out a bucket of toys from behind the machine.

"But… how will we know it works?" Sans asked. Suddenly, he felt something appear on his head. Not fall onto his head, not crawl onto his head, but just _appear_ on his head. He froze.

"Gaster." He said quietly. "What. Is on. My head."

Gaster's face brightened.

"Progress." He said, taking a toy truck off of his head and showing it to Sans.

"Wait." Sans slightly sputtered as he took it. "What?" The truck was a little cold, but completely undamaged. It was probably the most polished, brand new looking toy he had seen in a while.

"Did…" Sans trailed off as he squinted at it from every angle.

Gaster sifted through the bucket, eventually pulling out an exact copy of the truck. Sans watched in awe as Gaster put the truck into the machine and pushed about thirty buttons. He activated each lever, one at a time. With each one, the machine got louder and louder until Sans dropped the truck and covered his ears because of how frickin' loud it was. Gaster stopped on the last lever, closing his eyes and breathing deeply.

"Sans, please back away!" He yelled over the machine, gripping the lever harder. Sans took about two steps back.

Gaster breathed deeply again and pulled the lever. The machine suddenly made a really loud, really sudden _clunk_ that made Sans jump. Gaster ran out quickly, slammed the heavy door shut, literally picked up Sans, ran to the other side of the room, and gripped Sans in a hug to protect him with his body. Suddenly, there was a really bright flash of light, a blast of heat that was so hot even Sans was uncomfortable, and a blast of cold that made him shiver. The motor sound finally started to die down slowly. Gaster waited until it had gone completely quiet before he breathed a sigh of relief

"Uh… Gasty." Sans said, wiggling a little bit underneath him.

"Oh. My apologies." Gaster said as he let go of him and stood up slowly.

"What was that all about?" Sans asked as he lifted himself off the ground.

"I… I over reacted." He said, avoiding eye contact and straightening his glasses.

"Uh… It… It's cool." Sans said awkwardly. He was a little shocked at how... Intimate that was. Gaster wasn't the kind of guy who openly displayed affection like that. Then again, neither was he. Sometimes Sans forgot that Gaster created him, and was essentially his father.

Alphys suddenly burst through the door, looking terrified.

"Are you guys okay?!" She cried. "I-I f-felt that from all the w-way from upstairs!" She froze, her eyes drifting to the machine. Sans followed her gaze behind Gaster, only to find two _huge_ bone attacks blocking off Gaster and Sans from the machine.

"Jesus Christ." Sans gawked. He had only been able to make a bone attack that big… Maybe _once_? And he just made _two_ like it was _nothing_.

Gaster closed his eyes, brought his hand up, and slammed it down, pushing the bone attacks back out of existence.

"You… You really thought I was gonna get hurt." Sans said quietly.

"Are… _Are_ you h-hurt?" Alphys asked nervously.

"No… I'm fine." Sans said, absentmindedly brushing off his shoulder. "Gasty… You really don't need to worry about me… Really. I can protect myself."

"... Once again, my apologies. I don't doubt your abilities, Sans." Gaster said cooly, straightening his lab coat. He approached the machine and opened the door. A stereotypical cloud of smoke came wafting out like someone had thrown a chunk of dry ice in there. He began searching all around the inside of the machine. The toy truck was nowhere to be found.

"Did… Did it work?" Alphys asked timidly.

"... Yeah." Said said, realization just now hitting him. "Holy shit… Holy _shit_ it worked!"

"Indeed." Gaster said nonchalontly as he walked out of the machine. "But don't get your hopes up. That was a small, artificial, non-sentient object. And that was only sending it _back._ We still need to test if going _forward_ will work." He paused for a moment before letting his excitement finally show.

"But, I must say, we accomplished the seemingly impossible today." He said proudly, nodding at them both. "Fantastic work, everyone."

"Welp, I say we take a break." Sans stretched. "After all, we deserve it, right? We've been working… Down to the-"

"Sans, for god's sakes you've made that joke at least five times in the past week." Alphys moaned.

"C'mon, it's so fitting!" Sans teased, elbowing her in the arm.

Gaster pondered Sans's request for a moment before responding.

"I suppose. But I expect you here again tomorrow for more testing. Understand?"

"All right, Frankenstien. I got ya." Sans acknowledged before turning back to Alphys.

"Yo, what's that cutie show you were talkin' about earlier?" Sans asked. "We've both been workin' hard, how 'bout we take a load off and watch that?" Alphys literally squeaked in excitement.

"Oh my god! Ohhhh myyy _god_! I'm so glad you asked! I'll get us nice cream, okay? I'll meet you upstairs in a few minutes!" She dashed away before Sans could even react.

"Heh." He hummed. "I gotta go, she's not going to wait for me very long… Congrats, Gasty."

"Don't forget Sans, this is your success as well. Take pride in it." Gaster reminded him, putting a hand on his head.

"Yeah, yeah, I get it, boss." Sans said as he pushed Gaster's hand off of his head. "But I got some Anime to watch."


	5. Chapter 5 - The Scare

**WARNING: This chapter has a panic attack-esque scene in it. Please proceed with caution.**

"Sans! Ready your shield!"

Sans nodded, making a fist with his hand and punching upwards. A few bone attacks appeared out of the ground, just tall enough to make a temporary shield. The loud clunk of Gaster flipping the lever sounded, and the same process of a bright flash, hot air, cold air, then the motor dying down into silence. Once the last spurr sounded, Sans lowered his bone attacks back into the ground. Gaster did the same with his. He opened the door, inspecting the inside of the machine. Sans followed suit, looking around for any sign of the teacup they had sent through. It was nowhere to be seen.

"Where'd you send it to, Gasty?" Sans asked as he followed Gaster back out. He had to jog to keep up with Gaster's rediculusly long strides as he made his way to the table they kept in the room.

"It should appear somewhere on that table in approximately thirty seconds." He stated, eyes fixating on the table and starting the stopwatch he had in his hand. Sans copied him, watching intently on the table.

Have you ever heard thirty seconds of silence? Let alone, "if this dosen't work years and years of work will be for nothing" thirty seconds of silence? It's tense. Really tense. As in, your whole body freezes up to the point where it's painful.

Sans flicked his eyes between Gaster and the table. He was unmoving, squinting intensely, stopwatch gripped in his hand.

There was a little bit of a wooshing sound before the teacup popped into existence. But on the floor, not the table. Sans let himself relax as Gaster stopped the stopwatch, glancing down at it.

"Thirty-two seconds." He stated, putting it in his pocket. "It seems that the spatial and time accuracy are a little bit off. Sans, please put another object in the machine and change the coordinates-"

"Woah woah woah, what? You want me to use that god-forsaken hunk of metal?" Sans objected as he pointed at it.

"Yes. You know how, correct?" Gaster asked matter-of-factly.

"Well, yeah, but-"

"Then I see no reason why you shouldn't." he said, gesturing to the machine. "You said you can take care of yourself, correct?"

Sans sighed, as he started shuffling his way over. He sifted through the bucket, eventually finding a fancy-ass fork.

"Please shift the coordinates a little to the right and the time two seconds back." Gaster called, writing down the results of their previous test.

Sans nodded. Facing towards the entrance to machine.

Now, Sans didn't scare easy, he'd been faced with way too many dangers in his life and handled them like it was nothing. He had yawned in the face of imminent death before. He only had to lift his finger and he could evaporate someone with a fucking dragon-esque head.

But he never realized how terrifying this machine was until he looked inside with the mentality that he had to turn it on. Those intense flashes that happened? He feels next to nothing in ways of pain and temperature. One time he stuck his hand in fire once to see if it would hurt. It didn't. But he felt the heat from the machine. He felt the cold from it blast through him like other monsters had described cold before. If he didn't use his shield every time, he would probably lose his eyesight for a few minutes from how bright it was. And all that was with the door closed.

It just hit him that if he fucked up while he was in there, he'd be sucked in and flung through time and space for all eternity. He wouldn't even be able to die, he'd just be tortured by expanding and contracting matter. He'd watch timestream after timestream fly by his eyes in single instances until his head couldn't take it anymore, and then he'd just get pounded with more. He would be suspended in there until time itself ended.

He felt his breath catch as he gripped the fork, suddenly finding himself having a great need to not go in there.

"Is there a problem, Sans?" Gaster asked.

"N-no." He stuttered. "Hang on."

He slowly took a single step forward. It suddenly seemed way bigger than when he first saw it. It felt like it was moaning at him, screaming that it would swallow him whole and digest him for eternity. His hands began to shake when he took one more step forward. He was beginning to understand why Gaster flipped the first time they used it.

It was probably his imagination, but he felt like there was a breeze. A breeze going into the giant hunk of metal, sucking him in. He thought he might have even felt his jacket flutter around him.

He took a deep breath and placed his first foot inside the machine. He could've sworn his footstep echoed. He put the fork in the middle of the floor, not wanting to bring his other foot in. When he actually looked at the fork, he saw that he had bent it in half from gripping it so hard. Whatever. It'll still work. He reached up to push the first set of buttons. But he couldn't. Not with only one foot in. He was too short. He was too fucking short. He had never hated being so short in his life until this moment.

He swallowed as he placed his other foot into the machine. The darkness inside it felt like an actual physical weight surrounding him. He slowly pushed the first button. It lit up for a half a second. He clenched his jaw as he steadily went through the button process. He never realized how many buttons he had to push until just then. What was it, like, fifty buttons? Jesus. Once he finally pushed the last one, he rested his hand on the first lever.

He stood there and eyes squeezed shut, mentally yelling at himself to pull the goddamn switch. Gaster had done it before, so he could do it, right? But the only thing going through his head but the image of his screams of agony being instantly muted by the dimension that should never have been reached. His legs shook. He felt his soul pounding in his chest. Would it be silent? Or would it be so loud that his skull would crack? What would he hear? White noise? Screams of horror? His stomach dropped with each passing moment until he was having trouble breathing. He felt the terror rise higher and higher, sweeping over him as he started to sweat. Would he see everything? Would he see nothing? Would he be wiped from existence? Would he ever somehow make it back?

Would he ever see Papyrus again?

"Sans-"

Gaster's voice made him jump and he immediately pulled the lever.

The motor revved, making Sans cry out. He ran out of the machine, bringing his hand up and flinging it down, flipping the next switch with his telekinesis. He did the same for all the other switches, spastically slamming his hand up and down. Once he flipped the last switch, he slammed the door shut so hard that the clang vibrated in his head. He punched upwards, summoning a bone attack. He dropped to the floor, curling up into a ball and covering his head. The flash of light, heat, and cold went past, and the motor died down. Sans stayed his his panicked position, Panting heavily as his eye spouted out frantic wafts of blue smoke.

"Sans."

He didn't move.

"Sans." Gaster repeated. Sans felt a hand on his shoulder.

He didn't respond, his breath and entire body shaking, sweat and tears running down his face.

They both waited, the only sound between them was Sans gasping and the occasional sob.

After who knows how long, definitely too long, Sans calmed down to the point where he could sort-of talk. He sat up slowly and wiped his face off.

"Sorry." He mumbled, his voice scratchy.

"There's nothing to feel sorry for." Gaster reassured.

"It's just…" Sans said, putting a hand to his head. "I'd never been so scared before in my life."

"It's over now." Gaster said calmly. "You can put your shield away."

Sans glanced behind him, before suddenly turning around at the sight before him.

He had summoned a bone attack so huge that it had crashed through the ceiling.

His jaw dropped. Did… Did he do that?

He slowly brought his hand up to bring it down. It didn't budge. His face furrowed in frustration as he brought up a second hand. Still didn't move. He stood up, grunting with the effort. When it still stayed put, he growled angrily before summoning a blaster, making the bone disintegrate. He fell to the ground again, hunched over in exhaustion.

"I won't make you operate it anymore." Gaster said, placing a hand on his shoulder again.

"... Thanks, boss." Sans sniffed.

"You can go home." Gaster said. "Can you make it there by yourself?"

"... Yeah." Sans said, standing up.

* * *

Sans opened the door slowly, trying not to make a lot of noise.

"SANS! YOU'RE HOME EARLY!"

"Goddamnit." Sans muttered quietly. It's not that he didn't want to talk to Papyrus, it's that he didn't want to talk to anyone. He was even more tired than before. He had to walk all the way home because he had been too exhausted to use his teleportation, and he wasn't all that great at talking when he was tired, let alone after the episode he just had.

"DID SOMETHING HAPPEN? ARE YOU ALRIGHT?" He called, appearing out of the kitchen.

Sans tried to respond, but all that came out was his voice cracking.

Papyrus's expression dropped as he rushed over to Sans. He kneeled down, grabbing his shoulders.

"Sans, what happened?! You look terrible!"

Sans winced at the quietness in his voice. He could count how many times Papyrus had talked seriously on one hand, and they seemed to be becoming more and more frequent lately. He took a shaky breath.

"I'm… I'm havin' a b-bad day." He mumbled.

Papyrus squinted at him, knowing that he wasn't telling the truth.

"Sans, as your brother and protector, I want to know what happened so that I can help you."

"I… I just…" Sans trailed off.

Papyrus suddenly wrapped him in a big hug, surprising him. What was with everyone giving him hugs lately?

"Dude… I'm fine." Sans said, his voice wavering. "You don't need to hug me. I'm not feeling bonely. Ha ha. Get it? B-bonely…"

His face scrunched up, not being able to stop himself. He buried his face in Papyrus's shoulder, wrapping his arms around him and gripping his clothes, quietly sobbing. Papyrus gripped him tighter.


	6. Chapter 6 - Recovery

After an embarrassing three or so minutes, Sans finally started to calm down. He slowly pulled away from Papyrus, wiping his face off and avoiding eye contact.

"... Sorry, bro." he mumbled, awkwardly shuffling around Papyrus and trying not to rush himself as he went up the stairs.

"Sans, are you sure you're alright?" Papyrus called after him.

"Yeah… Yeah I'm good." He said so quietly that he couldn't even hear himself.

He quickly opened his door, rushed into his room, and closed it behind him. He let himself cringe.

Stupid, stupid, _stupid._

He fumbled across the room and plopped onto his bed, bringing the covers up over his head. _Why_ did he let himself go like that? Papyrus was the emotional brother who needed comforting, not him. Why did he just dump it all on him like that?! He didn't deserve it.

His self-guilting session was interrupted by a knock at his door.

"Sans, can I come in?" Came Papyrus's timid voice. God, he wasn't supposed to sound like that. He was supposed to be screaming about the Royal Guard and Puzzles. He was supposed to be mad at him for telling a joke or for being lazy.

The door opened anyway. Sans looked from under his blankets to see that Papyrus had brought him a glass of water. He didn't complain about how dirty his room was. That was a first. He walked through the ocean of dirty laundry and food wrappers like it wasn't even there. He placed the water on his nightstand before awkwardly placing his hands behind his back. Sans peeked the top of his head out from under his blankets.

"Do... You need anything?" He asked softly. Jesus. What had gotten into him?

"... No."

"Well, please tell me if you do. I will be listening."

Papyrus started to make his way back to the door when Sans stopped him.

"Wait."

Papyrus turned around, raising his brow expectantly at him.

"... Stay with me… Please..."

Papyrus smiled warmly, walking back and sitting at the foot of his bed.

"Of course."

* * *

Sans blinked open his eyes drowsily. When had he fallen asleep? Well, this wasn't the first time he had fallen asleep like that. He might actually have narcolepsy, now that he thought about it. He looked down at the foot of his bed, finding Papyrus knocked out cold. Thank God, he finally got some rest. He had been starting to worry that he might actually get sick if he didn't sleep soon.

Sans instinctively looked at the clock. It was about the time he would normally head out to sentry duty. He rolled back over. He did feel better after sleeping… But he still deserved a break, right? He was just starting to let his eyes droop back shut, when he suddenly shot up in bed.

Shit. He was gonna be late.

Tossed his blanket aside, scrambling out of bed and throwing his slippers on.

"... Sans... What are you doing…?" Came the sleepy voice of his brother. Sans froze and turned around slowly. Papyrus was rubbing his eye sockets and yawning as he sat up.

"Uhh… I have sentry duties… Remember?"

"Are you sure you're feeling well enough?" He asked, genuine concern in his voice. God, what did he do to deserve Papyrus?

"Yep. Feelin' chipper!" He said, giving him an overly enthusiastic thumbs up.

"... Alright." Papyrus yawned. "If you're sure."

"I'll be back soon." Sans said quickly, rushing out his bedroom door.

He closed his eyes and there was a _pop_. When he opened them again, he was right in front of the door to the ruins.

He raised his hand to the door excitedly, before he paused for a half a second.

Why'd he stop? He furrowed his brow, trying to figure out why he suddenly couldn't make himself knock on the door, when it hit him.

He was nervous.

Why was he nervous? He wouldn't even be looking at her face. But he began to worry anyway. What if she didn't laugh? What if she wasn't even there?

He sighed and made himself tap lightly on the door. He had nothing to lose, right?

"Knock knock." He said apprehensively.

"Oh! Who's there?!" Came her voice excitedly. He felt all his tension leave him at the sound of her voice.

"Atch."

"Atch who?"

"Bless you."

Her laughter swelled through the air, bringing a dorky grin to his face. This was exactly what he needed after what had happened earlier.

"Wh-what kind of sword does a skeleton use to fight with?" she choked through her laughter.

He froze. Was she seriously just about to make a skeleton joke. Was she _actually_ about to do this.

"What kind?" He asked, trying to keep his voice calm.

"Shoulder blades!"

* * *

"You don't seem to be as… Something seems off. Are you okay?"

Sans turned from his position of leaning back on the door so that he was facing it. What?! He felt happier than he had been in a while while he was joking with her. Did she know something?

"Uh… Why'da say that?" He asked nervously.

"I have… An intuition for these things." She explained.

"I… Today was just… Weird." He wasn't lying. It _had_ been really weird that day.

"Oh. I see. Well I would completely understand if you wanted to go home and-"

"No!" He exclaimed, immediately slamming his hands over his mouth. Why… Did he say that?!

"Uh… I mean…" He laughed nervously. "I'm… I'm having a good time! I'll be fine."

"Well, if you're sure." She said apprehensively. "I don't want you to feel like you're forced to be here."

"Nah, I'll be okay. Don't worry about me." Sans dismissed.

What was up with people caring so much about him lately?

* * *

The next day, Sans found himself back in the lab at the usual time. When he walked into the room with the machine, he found Gaster in his natural state of writing stuff down.

"Sup, boss?" Sans asked, knocking on the door frame.

"Ah! Sans. There you are." Gaster said as he turned around. "I'm glad you came today."

"What? You thought I wouldn't?" Sans said casually as he approached him. Gaster's face turned somber, making Sans feel kind of uncomfortable.

It was weird whenever Gaster showed that he cared. His default personality was the mysterious, serious scientist who was so enraptured in his work that he might as well have it as his relationship status on UnderNet. Gaster treated Sans as a respected apprentice more than his creation most of the time. But every once in a while, Gaster showed a soft side. He really did care about Sans and Papyrus, and when he expressed it, Sans was once again reminded that Gaster was his father. For some reason, it made him shiver.

"Sans… I understand if you don't want to operate the machine anymore." Gaster reassured. "But I need to know if you can still test the machine with me."

"What? Oh, yeah, I can still test with you. I just… I just can't turn it on." Sans explained.

"Excellent." Gaster said, touching his fingertips together. "I trust your judgement. Will you test with me now, then?"

"Sure, why not." Sans shrugged. "What're we testing today?" Gaster pulled a bucket of snails out from under the table.

"We're testing organic, living material today." Gaster said, picking up a snail from the top. "Based on our previous tests, there should be no problem with the machine. We just need to make sure something that is alive can survive the journey."

Sans stared at the snail. It's antennas moved around slowly. He knew that their previous tests proved that inanimate objects could pass through without being damaged at all, but he still couldn't see how it was possible that anything could survive the monstrosity that stood before him.

"Well, let's give it a shot, I guess."


	7. Chapter 7 - The inevitable

Sans didn't feel right about this. There was something about this test in particular that set him on edge. It was weirdly nagging, like static electricity going down his neck. He kept reminding himself that the tests they had done before had proved that nothing bad should happen. So why couldn't he shake off this feeling of dread?

Sans watched as Gaster placed the snail inside of the machine. It wiggled a little bit on the floor. It wasn't a sentient snail, it was the kind that _couldn't_ talk. Like the ones on the surface. But he could've sworn it looked like it was scared.

What... The _fuck_ was he thinking? It was a snail. It was a fucking snail. It couldn't be scared. It probably couldn't even process what was going on right now. He was probably so paranoid because he hadn't fully recovered from yesterday. Besides, he was in a creepy lab and about to operate a machine that shouldn't even exist. It was expected to feel nervous in that kind of environment.

Right?

Gaster continued with the usual process. He pushed the usual fifty or so buttons before resting his hand on the first lever.

"I'm sending it forward thirty seconds. It should land on the table behind you." Gaster said matter-of-factly. "Please ready your shield." Sans didn't move. He couldn't get over the fact that something felt really wrong.

"Sans, what is it?" Gaster asked upon looking at Sans. It wasn't until then that Sans realized that he was grimacing.

"... Are you sure this will work, Gasty?" Sans asked. He knew it would work. Why was he asking? What was up with him?

"Yes. We just need to test it to make sure." Gaster reassured him. Sans saw Gaster move to pull the switch.

"Wait!" Sans shouted. Gaster turned and raised his brow at him.

"Uh… I guess I just… Wanted to thank you… For everything." Sans said awkwardly. What? _What_ was he doing? Why did he feel the need to say this? What was wrong with him?!

"So…" He continued. "Thanks." Gaster formed a small smile on his face.

"You are welcome, Sans." He said gently. "But we must continue."

Sans nodded and took a deep breath. He quickly summoned his shield and squeezed his eyes shut.

The motor revved, making Sans's stomach drop. The next lever sounded, then the next, then the next. Each one raising more and more panic in Sans until he couldn't take it anymore.

" _Gaster, stop!_ " Sans cried out. But he couldn't hear him. It was too loud. It was too fucking loud.

The clunk indicating the last lever had been pulled sounded, making Sans actually cry out in panic. Gaster slammed the door shut, ran next to Sans, and summoned his own shield.

Have you ever felt something happen before it actually happens? Like, you woke up a millisecond before your alarm clock went off because you somehow _knew_ it was going to go off? Or you somehow knew that you were about to drop something even though you had a tight grip on it? It was like that. Sans felt it. He felt it _right_ before it happened.

He had never felt so fucking terrified in his entire life.

The machine made a screeching sound that was comparable to a thousand banshees crying simultaneously. Sans threw his hands to the side of his head, trying to block out the deafening screeching. The intense bright light, heat, and cold all somehow happened at the same time. Sans shook from the intensity of it. The sound of metal bending and breaking groaned through the air as the door collapsed into the machine. _Into_ the machine. It was sucked in. A hole had opened up into the unknown, unreachable dimension. And it was taking everything in with it.

What had they done.

What had they _done_.

The gravity shifted into the rift they had created. The G forces almost made him black out. Light itself seemed to fall in, making it almost impossible to see anything but the rift. Air literally formed abrasions on his face from how fast the pull of it was. Sans gripped onto the shield, his entire system shutting down with fear. Every sense he had was screaming. He was paralyzed with fear. The gravity kept shifting around the room, lights started flashing. The sounds were like waves through his head, rising and falling with that god-awful sound that he would never forget. The only thing he could think to do was to hold on. He held on to his shield as hard as he possibly could.

Everything in the room was flying in. The walls, the floor, blueprints, the furniture.

The table.

That _fucking_ table.

The table that was behind him flew through the air. He couldn't even react from how overloaded he was. The table slammed right into him, breaking his shield.

You'd think that given the circumstances, he wouldn't even be able to tell that he started falling because of how disoriented he was. But no, time slowed down to a crawl. He actually felt reality stop around him.

What… What was happening?

His head started clearing up as the lights and sounds stopped. He felt this weird sense of calm wash over him once his senses had fully returned. He looked around to assess his whereabouts. Chunks of drywall and paper floated around him, headed the same direction he was. Was he… Floating? He looked down to see his jacket was rippling around him like he was underwater. He rolled his eyes from one side of the room to the other, taking in everything around him until his eyes finally landed on Gaster behind his shield.

Now, Gaster was a man of few words. He knew how to get points across without needing emotions. Sans had never seen him emote more than a smile before, which in of itself was a rare sight. So it goes without saying that Sans had never even seen Gaster nervous before. Let alone afraid.

But Sans saw horror on Gasters face for the first time.

It snapped him out of his zen state. Time and fear slammed back into him like a wall. Before he could even try to hold onto something, he fell in.

* * *

There were colors.

There were colors he had never seen before. They pounded through his eye sockets right into his conscious mind. He saw so many deaths. So many births. So many victories. So many failures. They all flew through his head at the same time. It hurt. It was too much. But they kept coming. They kept coming. They kept shredding through his mind.

It felt like weeks.

For _weeks_ it felt like it happened. The physical torture. He tried to scream, but it was like a vacuum in space. A vacuum that sounded like hell itself. His breath was non existent. He felt his body be torn to shreds and then mashed back together in less than a second over and over again. He was stretched and pulled, crushed and compressed, exploding, imploding. His body was somehow dying and bringing itself back to life.

For _weeks_ it felt like it happened. The mental agony. All he could see was war and despair. Anguish always snuffing out any joy that might have arisen. All he could do was watch. Watch as families saw each other die, plagues destroy entire nations, weapons of mass destruction tear so many lives away.

He wanted it to stop. He couldn't take it anymore. He couldn't take this much pain. He wanted it to end.

He wanted to die.

But it wouldn't let him. It kept him just alive enough to witness everything it threw at him. It laughed at him. Laughed at his pain. At his tears. It echoed. Louder and louder until it was the only thing he could hear. It vibrated through him like a church bell. Ringing down to his marrow. The harder he struggled, the louder it got.

He couldn't keep up the strength to fight back. It drained his willpower to try, sucking out any ounce of motivation he had left. He started to let go. To give up. To succumb. His eyes rolled back into his head. He let his soul begin to escape his body, taking Sans with it.

* * *

A hand suddenly gripped his shoulder, yanking him out of the rift. He flew out of the machine, crashing onto the lab floor. The pain vanished. The horror left his vision. He gasped, taking in frantic gulps of air.

He was out.

He was alive.

It hadn't been weeks, it had been seconds.

He looked back to see Gaster, one hand gripping the machine as he dangled inside the rift.

" _Gaster!"_ Sans choked out, scrambling to help him. But he wasn't able to move an inch. He looked down at himself, his entire body was glowing orange and blue. Gaster was holding him in place with his telekinesis, preventing him from falling back in.

"Let me go!" He yelled as he struggled, managing to reach out one arm towards him.

Gaster's expression was peaceful as began to form cracks in his face, his entire head was falling apart. Gaster reached his other arm into the machine, grabbing the time and space manipulator. The thing that had taken them so many years to make.

"... No. No, _no, no, no! Don't do it!_ " Sans cried, struggling harder than ever.

Gaster looked back at Sans and spoke in the language. The tongue that was supposed to be forgotten before the earth was even created.

"Take care of Papyrus."

" _DAD, NO!_ "

He ripped the Manipulator out of the machine and the rift disappeared, swallowing Gaster with it.


	8. Chapter 8 - Remember

**WARNING: There is a severe panic attack-esque scene in this chapter. Please proceed with caution.**

When Sans opened his eyes, everything was blurry. His vision was blurry, thoughts were blurry. He took a second to figure out where he was. His hands found rubble underneath them. His ears were ringing. The ground felt like it was shifting underneath him. The right side of his head was pounding. Clearly he had just been pummeled by something. Maybe he fell.

He grunted as he sat up, holding his head in his hands. As his vision started to clear, he noticed a lamp in the corner of the room flickering eerily. Being the only source of light that survived, it did next to nothing to help him see. But he eventually managed to get enough night vision to see the room.

He found himself in a dystopian-esque version of the lab. Furniture was broken and thrown all over the room, the walls and floor had been torn apart, papers and blueprints were shredded and scattered all over the floor, and the bent and broken remains of the machine were piled in the corner.

Sans slowly stumbled to his feet, barely able to hold himself up. He kept holding

his head as he dizzily made his way towards the machine.

"Gast-er?" He croaked.

It had collapsed into itself. Giant holes were all over it, buttons were missing, levers had been ripped in half. The entire back half of it was gone.

"Gasty?" Sans's voice wobbled as he fell against the entrance. "It's… It's over. The rift is closed. You… You can come out now."

Nothing happened.

"C-c'mon, Gasty." He let his hand fall to his side. "We need to write down the results. Try again, yeah?"

Silence.

"What was that thing you said?" He said, hearing his voice echo through the destroyed room. "Uh… Failure is just one step closer to figuring out the truth or some shit like that?" He laughed nervously. "Yeah… We… We just need to rebuild it! Start over!"

The flickering lamp sparked as the bulb burned out.

"... Gaster?"

Sans felt his way into the machine.

"... Dad?"

A piece of wire fell from the ceiling.

"Dad. C'mon, Dad." Sans said quietly, his voice breaking. He pushed the first buttons he saw, pressing them at random. They didn't light up.

"We… We need to help Asgore, remember?" He started pressing the buttons harder. "Save Asriel and Chara… Bring back the Queen… Bring back harmony between monsters and humans…"

"It… It's what we worked so hard for, right?" His shaking hand grabbed the first lever and shoved it downwards. Nothing.

"... C'mon. Don't do this." Sans felt tears fall down his face. "It's _not funny_."

He flipped the switch again. And again. And again.

"It's. _Not. Funny!_ " He said, raising his voice and forcing out each word with each flip of the switch.

He tried it one last time, pulling it as hard as he could. It clanged loudly, but nothing activated. He started backing away from it slowly.

"... Oh god... Oh god no…"

He went to the next switch, frantically pulling it up and down.

"Stop it… Gaster stop it!" He yelled, pushing every button he could within his reach.

Sounds of panic escaped him as he moved from switch to switch, pulling them as hard as he could, slamming his hands on the buttons in between. Nothing was working. _Nothing was working._

 _Dear god nothing was working._

He launched out of the machine and into the lab, scanning hurriedly for any pieces of the machine that had broken off. He threw aside what used to be a chair, frantically sifted through papers, searched in every crevice.

He couldn't find anything.

It had all been sucked in.

He fell back onto the wall he was next to, panting in exhaustion. He squeezed his eyes shut and tears lined his breath.

"Dad…"

He suddenly inhaled sharply, clenched his teeth, and ran back into the machine. He growled violently as he pounded all the buttons and flipped all the switches at the same time, slamming his hands down as the machine flashed blue. The ceiling groaned as it collapsed down into an even more severe angle.

But nothing turned on.

He fell on his knees in defeat, his breath shook heavily as tears started to fall on the floor.

"No… No, no, no! _Come back!_ " He suddenly wailed, banging his fist against the metal. "Come back… Please..."

He didn't even have enough time to start really sobbing before he heard Alphys.

"Sans?" Came her voice from the hall. "I'm back with the-"

Her words were cut short as she gasped when she entered the room.

"What…" She looked around the ruins of the room until her eyes landed on Sans.

"S-Sans...? Oh my… Oh my god." She rushed over to him and dropped onto her knees.

"What… What happened?" She asked quietly as she put a hand on his shoulder. He froze under her touch, his whimpers coming to an abrupt stop. He slowly looked up at her. She withdrew her hand from him, blushing in embarrassment.

"Alphys… Alphys _you gotta help me_!" His voice cracked as he grabbed her shoulders. She squeaked in surprise.

"G-Gaster-The-machine-We-"

"Sans, s-slow down! I can't understand you!" Alphys interrupted, jumping out of Sans's grip. "W-what are you t-talking about?!"

"The-the machine failed, Gaster fell in!" He fumbled over his own words. "You gotta help me get him back! _Please_!"

"What?!" She yelped. "What are you talking about?! Who's Gaster?!"

"... _What_?"

Sans suddenly felt a burst of rage surge through him at her words. He felt the puffs of blue smoke rush out from his eye as he jumped up from the ground.

" _What the fuck do you mean, 'who's Gaster'?!_ " He yelled at her, clenching his fists as they sparked, his voice morphing at his anger. " _I'm NOT in the mood for jokes!_ "

Alphys cried out in terror and shielded her face from him. Sans realized what he had done as soon as he saw her fear and immediately forced himself to calm down.

"Oh god Alphys… Alphys, I'm so sorry." He said quietly as he slowly reached out to her. She flinched as she scurried half way across the room from him. He felt guilt twinge at him.

"Alphys, I'm sorry." He called from across the room, taking a step towards her. "But Gaster is in there, I… I need your help to get him back."

"B-but…" She whimpered. "I… I d-don't know what you're t-talking about…"

Sans stopped in his tracks. He could hear the sincerity in her voice.

"... Alphys? You… You really don't know?"

"No! I don't!" She cried.

"He… He's the royal scientist, remember?" He took a few more steps towards her. "You… You helped him build that machine over there." He pointed at the god-forsaken contraption.

"I… I've n-never seen that machine before in my life!" She claimed. "T-there is no royal s-scientist, Sans! What h-happened to you?!"

Sans was about to protest, when he felt something chemically shift in his head.

She… She was right. There was no royal scientist. That machine in the corner is a hunk of metal that he'd never seen before. What was he talking about? There was no Gast-

" _No_!" He suddenly shouted, slamming his hands on the side of his head.

"No… No, no, _no!_ " He shook his head angrily. "Gaster is _real!_ He… _He created me_!"

His eyes widened as he began to realize what must have been happening.

Gaster fell into time and space itself.

"Oh… Oh god." He felt terror rising in him. "Oh my god, no."

"... Sans?" Alphys asked timidly.

He immediately shot into action, closing his eyes and quickly teleporting to his house. As soon as he opened them, he frantically started running around the house, looking for pictures of Gaster, something Gaster owned, _anything_ related to Gaster. He started demolishing the living room. Ripping apart the couch, knocking over the TV, flipping the table, looking inside every drawer, under every surface.

"SANS, IS THAT YOU DOWN THERE?" Papyrus called from his room.

He froze upon hearing Papyrus. He didn't even wasting time walking up the stairs. He just straight up teleported to Papyrus's door and burst into his room.

"Papyrus!" He cried, making Papyrus jump. He rushed up to where he was sitting at his computer desk.

"Papyrus, please, for the love of god, _tell me you remember him_!" He cried, grabbing his arms and gripping them tightly.

"SANS, WHAT ON EARTH ARE YOU TALKING ABOUT?" Papyrus asked, raising his brow. "ARE YOU OKAY? YOU SEEM TO BE EXTREMELY UPSET ABOUT SOMETHING."

"Gaster!" Sans yelled as he shook him. " _Please tell me you know who he is!_ "

Papyrus furrowed his brow in concentration, thinking hard.

Sans let go of Papyrus and hung his head in defeat. "You… You don't remember, do you?"

"... THE NAME SEEMS FAMILIAR." Papyrus stated. "ARE YOU LOOKING FOR THIS PERSON? ARE THEY LOST?"

"Woah, wait, you remember?!" Sans asked, flinging his head back up in surprise.

"I DON'T KNOW WHO THIS PERSON IS." Papyrus maintained. "ALL I KNOW IS THAT I'VE HEARD THAT NAME BEFORE. SANS, WHAT'S WRONG? YOU LOOK EXTREMELY DISTRESSED."

Sans suddenly felt the shift in his head again. Gaster's existence started blurring out of focus.

"No!" He yelled, banging his head with his fists. "Not again! _No_!"

He ran out of Papyrus's room in a blind panic, dashing into his. He dove into his dump of a room, flinging socks and tearing through garbage. C'mon… There had to be a picture of him or _something_.

"SANS, WHAT ARE YOU DOING?" Came Papyrus's voice from the hall.

"Hang on, Paps!" He called out, hysteria edging into his voice

Once again, he scoured through everything. He crawled under his nightstand, flipped over his mattress, and looked inside every sock. All of it for naught.

He fell onto the floor in exhaustion. He had looked through the entire house now, and the memories he had of Gaster were beginning to slip out of his grasp. He cried out in panic and pounded his fists on the sides of his head. He couldn't forget. _He_ _couldn't forget._

Don't forget when he first succeeded attempting telekinesis and Gaster had patted him on the head and gave him a patient smile. Don't forget how he used to copy him when he was little, drawing scribbles on a piece of paper next to Gaster while he was taking notes. Don't forget when Gaster made Papyrus, bringing true joy into his life for the first time. Don't forget when he gave them the house that they lived in-

His breath caught in his throat.

He hadn't looked through the _entire_ house.

He blinked his way into the back room. God, he hadn't been in here in forever. There was next to no chance that something was in here, but he had to try.

He yanked open the first drawer, almost breaking it from how hard he pulled. Just his luck, the old photo album slid out from the back. He completely forgot that he had it. He flipped through the pages, his eyes darting between the pictures.

Nothing.

Not a _single_ picture had Gaster in it.

He flipped through it again. C'mon, _c'mon._ There _had_ to be _something_.

His eyes suddenly caught a picture of himself and Papyrus. Something was… Off. The picture seemed wrong. They were both smiling, but an awkward distance apart from each other. Sans seemed to be leaning towards the empty space for some reason. Papyrus's arm was held out beside him, as if it were wrapped around someone.

Sans's eyes widened as he finally realized.

Gaster literally had disappeared from the picture.

"Fuck! _Fuck_! _FUCK!_ " He screamed, throwing the photo album across the room.

He was disappearing from existence, and Sans couldn't stop it.

" _Remember!_ " He yelled at himself as he started clawing at his face in a fit of hysteria. " _DON'T FORGET HIM!_ "

He gasped loudly as pain suddenly shot all the way up his spine to his skull. He fell over onto the counter, being consumed by convulsions. His entire body started glowing blue as he desperately gulped for air and cried out, sweating and sobbing violently.

His body was literally rejecting Gaster.

" _N-o!_ "

He forced his vibrating arm to pull open the drawer next to him, barely managing to pull out a piece of paper and a pen.

"D-don't you forget." He choked out, holding his hand still with his other arm while he scribbled.

He couldn't draw for shit. Let alone while he was shaking so badly. Tears and sweat dripped on the paper, smearing some of the drawing.

But none of that mattered.

He collapsed onto the floor when he finished it, gripping the drawing tightly as he curled up into a ball.

"Don't you forget."


	9. Chapter 9 - Getting help

**Author's Note: WARNING: This scene contains basically torture. Please proceed with caution.**

"SANS?" Papyrus called, rapping on Sans's door. "YOU'VE BEEN IN YOUR ROOM FOR OVER FIVE MINUTES WITHOUT MAKING A SOUND. ARE YOU ALRIGHT?"

No response.

Had he fallen asleep? He'd been known to randomly fall asleep before. Especially when he was supposed to be working. But had just been so frightened minutes before...

Papyrus turned the knob and opened the door slowly. His eyes scanned his brother's room, looking for any sign of him.

He wasn't there.

What?! Where did he go?! He never saw him leave his room! How was he gone?!

He shot through the door and started frantically digging through the dirty laundry and looked under his bed. Still nothing.

"SANS! WHERE ARE YOU?!" He ran out of the room, raising his hand to his mouth as he called out to him.

Still no sound.

He bit at the tips of his fingers in worry, dashing down the stairs and into the kitchen. He looked under the sink. Nothing. Inside the fridge? He was small enough to fit in there, right? No. Under the couch? Behind the couch?

No matter where he looked, Papyrus couldn't find him anywhere.

His worry swelled as he held the sides of his head, trying to think logically. Did he somehow manage to get out of the room without him seeing? That's practically impossible! Unless… He had a secret passage in his room! That must be it! He's always up to ridiculous shenanigans like that. It's entirely possible that this was the case!

Just as Papyrus was about to go back to Sans's room for closer inspection, he finally heard Sans, sending relief rushing through him. His low voice started emanating from the back room, echoing through the house.

But his relief immediately snapped away when he realized that it was unrelenting screams of agony.

"SANS!" Papyrus cried out in fear, sprinting to the front door.

He ran around to the back of the house so quickly that snow flew out behind him from under his feet. When he literally kicked down the door, he found Sans laying facedown on the floor, shaking as blue flames surrounded his body and the area around him.

"SANS! WHAT HAPPENED?! WHAT'S WRONG?!" Papyrus cried, rushing to Sans's side and kneeling next to him.

When he didn't respond, Papyrus gingerly turned Sans over onto his back so that he could see his face.

He immediately wished he hadn't.

Papyrus saw pure, raw, unadulterated pain on Sans's face for the first time. His mouth was open in a desperate attempt to scream, but only strangled chokes came out. He could see the frantic struggle for air as he heaved his chest and made wheezing sounds. His left eye spouted a constant stream of smoke. His convulsions were frighteningly violent, his head repeatedly smacking hard against the floor.

"SANS!" He shrieked, scooping him up in his arms. His body rattled against Papyrus, sparking small flames all over him.

"I… I HAVE TO GET HELP!" He cried, already sprinting out the door.

* * *

Papyrus hammered on the door unceasingly. He could feel Sans starting to burn up, and the flames around him were growing bigger and beginning to engulf Papyrus.

"What the _fuck_ Papyrus?!" He heard Undyne growl as she yanked open the door to her house. "I already told you that you can't join the-"

"UNDYNE! P-PLEASE HELP!" Papyrus sobbed as Sans choked out a particularly brutal sound.

"What… What the _hell_?!" She exclaimed, stepping to the side to make room. "Get in here!"

He walked into her house timidly. He could feel the heat of his fever getting worse as he sniffled pathetically.

"In here." Undyne said as she opened the door to her room. "Put him on the bed, quick."

He hurried into her bedroom, gripping Sans tighter. Undyne flipped on the light, illuminating the room. Papyrus scurried to the side of the bed and carefully released Sans from his arms and onto the sheets. His arms fell over limply and plopped onto the mattress pathetically. Flames already began to spark on the sheets.

"PLEASE! UNDYNE!" Papyrus suddenly cried as he rushed over to her. He clasped his hands together in a begging manner as he invaded her personal space. "YOU'RE THE ONLY ONE I COULD THINK OF FOR HELP! PLEASE SAVE HIM! SURELY YOU KNOW WHAT TO DO! I DON'T KNOW WHAT HAPPENED! HE'S IN SO MUCH PAIN! HE CAN'T BREATH! HE-"

"Papyrus! _Papyrus, stop_!" Undyne yelled, slapping her hands onto a strong grip on his shoulders. "Listen, this is your first royal guard training lesson, okay? Rule number one: panicking _always_ makes everything worse. Calm down and clear your head."

Papyrus froze at her words, letting them sink in. It took him a couple of seconds before he slowly straightened himself up tall.

"Good." She affirmed, letting go of him. "Now take a deep breath."

He closed his eyes, breathed in, and released.

"Great job." She praised. "Now, listen. I have Alphys's number. She was a med student before she got into that hardcore science stuff. I'll call her. She'll probably be here in less than ten minutes. Now, rule number two: _never_ leave someone in need behind. Stay by his side while I go call her, okay?"

Papyrus nodded stiffly.

"And _don't_ panic." She added as she walked back out the door.

Papyrus waited a few seconds before he slowly shuffled his way back to the bed. Flames were starting to spread across the sheets, and Sans's cries had been reduced to a low stuttering. But he was still gasping and shaking, and his eyes were still screaming.

Papyrus kneeled next to the bed, reaching his hand through the flames and taking hold of Sans's hand. Papyrus jumped slightly when Sans returned the grip tenfold.

And they sat there like that. Papyrus watched as his brother writhed and in agony.

And there was nothing he could do.

It took too long for Alphys to arrive. It took much too long. He couldn't handle it any longer. He was on the verge of having a breakdown, when Alphys burst in with a giant bag.

"I'm so s-sorry!" She fumbled. "c-came as s-soon as I could!" She suddenly stopped in her tracks upon the sight before her.

"... Dear God. What happened?!"

"He doesn't know." Undyne answered for him as she walked into the room. "Try to ask as few questions as possible. He's pretty freaked out."

"O-okay." Alphys nodded. She placed her bag next to Papyrus and started digging through it.

"H-how long has he b-been like this?" She asked as she wrapped a stethoscope around her neck.

Papyrus didn't take his sight off of Sans, who's eyes were starting to roll back into his head.

"I guess I'll answer the questions." Undyne sighed. "Let's see… he would have come over here as soon as it happened… and his house is a half an hour away if you walk… And he probably ran… And it took you ten minutes to get here… so around twenty five minutes?"

Suddenly, Sans violently coughed up blue liquid, spilling it all over himself and the sheets.

"SANS!" Papyrus cried, grabbing Sans's arm instinctively.

"Alrighty. Sorry Papyrus, but you'll only make things worse from here." Undyne said as she pried his hands off of Sans. "You're gonna have to leave the room while Alphys takes care of him."

"WHAT?! NO! I'M NOT LEAVING!" Papyrus refused, leaning over Sans to cover him from her.

"Yes, you are." She said calmly as she suddenly lifted him off of the ground.

"WHAT ARE YOU DOING?!" He yelled, struggling to get out of her grip. "PUT ME DOWN THIS INSTANT!"

"Nope." She stated, placing him on the floor outside of her room. "Wait here for a little while, okay?"

She slammed the door on him, locking it behind her.

"UNDYNE! LET ME IN!" Papyrus demanded as he scrambled up from the ground.

"The more you scream, the more distracted Alphys will be." Undyne said through the door. "And the more distracted she is, the longer it'll be until he's better. So keep it down, will ya?"

Papyrus clenched his teeth as he stamped his foot. He plopped back down on the ground, sitting against the door.

Sans suddenly made a really long, really desperate sounding gasp, and Papyrus finally broke down into tears, his face falling into his hands as he silently sobbed.

* * *

God, he had such a headache.

It pounded behind his eyes and spread to the back of his skull. He brought a hand to his head as he grimaced.

He tried to open his eyes, but the light was blinding. It sent another wave of pain through his head.

"Christ." He moaned quietly as he winced hard.

"OH MY GOD! SANS! YOU'RE AWAKE!"

He was suddenly shoved into a bear hug, shooting pain through him. He huffed out the air that Papyrus squeezed out of him, but eventually returned the hug.

"Papyrus! B-be careful!" Came Alphys's voice. "He hasn't f-fully recovered yet!"

"It's cool. I'm feelin great." Sans said into Papyrus's chest, patting his back. His voice sounded like he gargled a cheese grater.

"I might even be feeling a little _humourus_ too." He added.

He felt Papyrus freeze at his comment before placing him slowly back on the bed.

"ALPHYS, PLEASE PUT HIM BACK TO SLEEP AGAIN."

Sans chuckled softly, which accidentally induced a sudden coughing fit. Each cough was like a nail to the head.

"Guh- God-" He choked out between wheezes.

"Hokay. Time to give him some space." Came a voice he didn't completely recognize.

Sans realized he hadn't really opened his eyes all the way yet. When his coughs calmed down, he slowly sat up and barely opened his eyes, letting them get used to the light.

He found himself in someone's bedroom. The bed he was laying on was blue with waves printed on it, making it look like an ocean. Papyrus stood by the bed, worried from his coughing. Alphys was biting her claws at the foot of the bed. And… Was that Undyne leaning against the doorframe?

"Where-"

"You're at my place." She interrupted, striding her way next to Alphys. "Papyrus brought you over here when you got really sick. Good thing he did, too. We're not sure you would have made it without good ol' Alphys here!" She softly punched Alphys in the shoulder, making her yellow face burn into a bright red.

"Uh- you- your b-body was going through extreme r-rejection." Alphys stuttered, scratching the back of her head. "Do you h-have any idea why?"

"... Rejection? Fu-"

His eyes flicked over to Papyrus, who was now watching him intently.

"Uh, Heck if I know." He corrected himself. "I mean, the last thing I remember was that I was looking for… Something. I'm not sure what, though." He absentmindedly stuck his hand into his coat pocket.

Wait.

"... Where's my coat?" He asked quietly.

"I… I had to take it off." Alphys explained. "You… You were running a really high fever-"

"I need it. _Give it back_." He suddenly demanded.

Alphys was taken aback by his sudden hostility. She jumped backwards.

" _Hey_! Listen up, bucko." Undyne sneered at him as she placed a hand on Alphys's shoulder. "You would have _died_ if she didn't take it off. You should be _thanking_ her."

"But I need it back!" He said, finding himself starting to panic.

"ALPHYS, MAYBE YOU SHOULD-"

"Y-you s-still haven't f-fully recovered f-from your f-fever!" Alphys defended herself, hiding behind Undyne. "It'd b-be dangerous for y-you to w-wear it now!"

"I promise I won't wear it! _I just need it_!" He exclaimed, his voice breaking slightly.

Undyne looked down at Alphys and raised an eyebrow.

"... O-okay." Alphys resigned. "I'll go g-get it."

She scurried out of the room, leaving Undyne and Papyrus with him.

"Why'd you pick on her like that, huh?!" Undyne growled, her hands forming into fists.

"UNDYNE… I DON'T THINK HE WAS TRYING TO BE MEAN." Papyrus defended for him. "HE'S BEEN REALLY SICK AND-"

"But he didn't have to _scare_ her!" She yelled at Papyrus.

"Hey!" Sans shouted back. "Don't yell at Papyrus like tha- Oh _god!_ " He slammed his hands into his face as a baseball bat cracked him in the back of the head.

"SANS! ARE YOU OKAY!?"

He growled in frustration, waiting for the pain to pass. When it started to dull, he took a deep breath.

" _Don't_ yell at my brother like that." He finished, letting his hands fall from his face and glaring at Undyne.

Alphys suddenly opened the door with Sans's coat.

"I'm back!" She proclaimed as she approached the bed and handed Sans his coat. He snached it out of her hands and buried his face in it.

Why… Did he do that? As soon as he grabbed it and his anxiety calmed down, he realized how weird it was that he felt a desperate need to have it. What was up with the coat? Why did he want it so badly? Was it important somehow?

Whatever. He had it now and he was okay.

"Papyrus, can you walk out of the room for a second?" He said into his coat.

"WHAT? WHY?"

"I need to ask Undyne a few questions. I promise it won't be long. Can you just do it? For me?"

There was a couple seconds of silence. Before Papyrus answered.

"... OKAY. PLEASE STAY SAFE." He said.

He waited until he heard the door close before he started talking.

"Now, I was barely coherent earlier." He said calmly. "But I drifted in and out of consciousness, and heard a few things here and there."

He slowly lifted his face out of his coat to make eye contact with Undyne.

"What did you say in front of my brother?"


	10. Chapter 10 - Dreams suck

"Uh… This… This should help with the pain." Alphys said quietly, pulling out a syringe from her bag.

"ALPHYS! PLEASE DO BE CAREFUL." Papyrus reached out to her nervously. "MAKE IT AS PAINLESS AS POSSIBLE. HE'S ALREADY BEEN THROUGH A LOT..."

"I'll m-make it quick." She assured, filling up the syringe with painkillers.

"It's just a shot, Papyrus." Undyne said, rolling her eyes.

"HAVE YOU EVER HAD A SHOT BEFORE?!" Papyrus stamped his foot. "IT… IT REALLY HURTS."

"It's cool, bro." Sans said, holding out his arm to Alphys. "It can't be any worse than this god-awful headache I have."

"I-It's a migraine." Alphys corrected timidly, taking his arm.

"Same difference." He shrugged. The needle pierced his bone and injected the medicine into his marrow. He was right. It was next to nothing. The pain in his head faded away almost instantly, making him actually sigh in relief. He winced a little bit in embarrassment from his reaction.

"WOW SANS! YOU DIDN'T EVEN BLINK!" Papyrus clapped.

"Jesus, Papyrus." Undyne sighed, putting a hand to her head. "It's _just a shot."_

Sans cleared his throat loudly and glared at Undyne. She rolled her eyes again.

"Is he good, Alphys? Do you need me to get anything else for him?" Undyne asked, walking up to Alphys, her arms folded.

"I WILL ALSO HELP, IF IT IS NEEDED!" Papyrus proclaimed.

"Uh… No. He's good." Alphys said, putting away her medical supplies. "He… He just needs to rest… And get some sleep."

"Great!" Undyne exclaimed, clasping her hands together. "How 'bout we go watch some anime, then? I wanna watch the one with the swords again!"

"Oh! O-okay!" Alphys lit up. "Sure!"

"Are... Are you okay if we leave you here for a little while?" Alphys asked, turning to Sans.

"Yep." He said, stretching. "I could really use a few winks."

"Okay." Alphys nodded. "Let's go, Undyne."

"Sweet!" Undyne said loudly, fist pumping. "I'll go get some food. You want spaghetti?"

"Sure! I always love everything you cook!" Alphys beamed.

"... SPAGHETTI?" Papyrus asked slowly. "YOU'RE... MAKING SPAGHETTI?"

"Yeah! Do you wanna help?" Undyne asked, waving him over to the door.

"UM…" Papyrus shrunk back timidly. "I… I DON'T KNOW HOW."

"No problem! I'll teach you, okay?" She offered, already halfway out the door. "Now c'mon already!"

"REALLY?! WOWIE! I CAN'T BELIEVE THE CAPTAIN OF THE ROYAL GUARD IS TEACHING ME HOW TO COOK!" He cheered, following her out the door.

Papyrus suddenly froze in place, slowly looking back at Sans in apprehension.

"I'll be fine, dude." Sans assured, waving him off. "Go knock yourself out."

"IF YOU'RE SURE." He said cautiously, flipping off the light switch to the room. "I'LL LEAVE YOU TO SLEEP, THEN."

"Don't burn the house down." Sans called after him as he closed the door, leaving him in serene darkness.

He rolled over in the bed and let his eyes droop shut, welcoming the unconscious embrace that was sleep.

But he suddenly felt the strange need to check his coat pocket.

He shifted a little, brushing off the urge as paranoia. But it rapidly started growing worse. The feeling scratched at the back of his head, nagging at him to look. He grimaced as he grabbed the pillow and shoved it over his head. Why was it so hard to get some sleep _now_? He'd fallen asleep standing up before, for god's sakes. And yet, here he was, lying on a surprisingly comfortable bed after his body had gone through extreme stress, and he couldn't go to sleep because he might have something in his coat pocket.

He sighed in defeat, reaching over to Undyne's nightstand and switching on her lamp. He didn't notice until that moment that the lamp had a picture of a yellow lizard on it.

He reached over on the other side of the bed where the coat lay and dragged it over to him, yawning as he fumbled it around, trying to find the pockets.

He found the opening for one of the pockets and stuck his hand inside. There _was_ something in there. He pulled it out.

It was one gold.

Was that it?! He was so worried about forgetting he had enough money to buy two french fries? He threw his hand into the other pocket, hoping there was _something_ of significance in it.

He heard a crinkling noise as his hand hit paper.

… When did paper get in there? He hardly wrote anything unless he really had to remember something. He pulled it out to find a crumpled ball. He smoothed it out on the covers. Something on the paper revealed itself as it unfolded.

Thank god he saw it when no one else was in the room.

His breath caught in his throat at the image on the page. It was an awful drawing of Him, Papyrus, and… That was…

"Oh god." He gripped the paper tightly. "Oh _god._ "

Bits and pieces of memories flooded back to him. Asgore's request, the machine, the fall. Even a vague memory of who he was came back to him, a blurry image of his face appeared in his head.

If he wasn't so hopped up on every drug known to monsterkind, he probably would have had a panic attack.

"... Alphys." He called out quietly.

No response.

"Alphys!" He called louder, shoving the drawing back into his coat.

He heard frantic footsteps scamper up to his door before she burst into the room.

"What?!" She squeaked nervously, flipping the light switch back on. "W-what's wrong?!"

"Please knock me out." He croaked, squeezing his eyes shut.

"What? Are you still in pain? Why-"

"Just _do it_!" He cried.

"O-okay!" She squeaked, fumbling as she opened the medical bag by the bed.

"I n-need to be out for a few days." His voice shook. "At _least_."

"B-but…" she hesitated. "That many sleeping pills would kill you…"

"Just please, for the love of god, _put me out._ " He pushed, his voice getting more frantic.

"... Well…" She poured a few pills in her hand from the bottle. "I guess I could make it so that-"

" _Do it._ " he swiped the pills from her hand and swallowed them dry. He put the pillow back over his head and squeezed his eyes shut.

"SANS? WHAT'S WRONG?" He heard Papyrus's voice through the open door.

"Ah, h-he, he wanted to sleep." Alphys answered for him. "So I gave him some medicine to help."

"... I SEE." Papyrus's voice was already starting to get further away. This was some heavy stuff she gave him. Probably infused with magic, thank god.

"So… he's probably really tired now." Alphys explained. "We should probably let him-"

He was out before he could even hear her finish her sentence.

* * *

The dreams were probably worse than what would have happened if he had stayed up.

He opened his eyes to find that he was in the lab, sitting on his desk and facing forward. He tried to look around the room, but he quickly found that he couldn't move his head. He tried to lift his arms. He couldn't. His legs? Nope. He couldn't even wiggle his toes. It was like someone welded him to chair.

The man suddenly appeared in the doorway, standing tall and confident. His face was pixelated and blurry, making it almost impossible to see. Sans watched as the man turned to him, looking down on him as he approached. He found himself intimidated by the man. He tried to shrink backwards, forgetting that he couldn't move.

When the man spoke to him, he spoke in... The language. His voice was garbled and morphed.

"Why?" He said angrily.

Sans tried to speak, but nothing came out.

"Why didn't you save me?"

Again, he tried to choke out sound, but to no avail.

The man suddenly slammed his hands on the desk, his face landing less than an inch away from Sans's. He tried to jump back away from him. He still couldn't move.

" _ **WHY DIDN'T YOU SAVE ME?!**_ " He screamed at an impossible volume.

A surge of fear rushed through him as the words deafened his hearing. His ears started ringing. He tried to cry out. He couldn't make a sound. He tried to cover his face. He still couldn't move.

The man grabbed Sans by the shoulders, lifting him out of his chair and shaking him violently. Sans could read his mouth saying "Why didn't you save me?" over and over. He tried to close his eyes to block him out. He couldn't close them.

The man threw him across the room, slamming him against the wall. San's vision went out when he plummeted to the ground.

It took him a few seconds to realize that he could move again. He gasped loudly as he scrambled to sit up.

He frantically flung his head around, trying to look for where the man was. But found himself in an entirely black room, and the man was nowhere in sight.

" _It's your fault."_ He heard a genderless whisper from behind him. He jumped in surprise and turned his head toward the sound. No one was there.

" _He's gone now."_ He heard to his right. He whipped his head around. No one was there.

More and more whispers began to fill the air around him.

" _You could have saved him."_

" _After all he did for you."_

" _It's your fault."_

" _You'll never see him again."_

" _He's in a never ending torment."_

" _It's your fault."_

He spun around frantically, trying to find the source of the words. He ended up making himself dizzy. He fell onto the floor on his hands and knees.

" _You've failed him."_

" _It's your fault."_

They were getting closer.

" _You could have saved him."_

" _It's your fault."_

" _You could have saved him."_

" _It's your fault."_

He squeezed his eyes shut as he curled into a fetal position and covered his ears, desperately trying to block out the whispers.

" _It's your fault."_

" _It's your fault."_

" _ **It's your fault."**_

" _I'm sorry!_ " He shrieked. " _I'M SORRY!"_

"Sans?" Came a gentle voice.

The whispers ceased abruptly at the voice. Sans's cries of panic slowly diminished as he opened his eyes. He lifted his hands off of his head and sat up slowly, looking around for the voice.

The room was still void of anyone but himself. He waited until he calmed down enough before he stood up, brushing off his coat.

His… Coat? He wasn't wearing that before. He looked down. It was blue and fuzzy. Where did it come from? He's never seen it before.

"I felt… Guilty." The voice echoed. "Guilty for how much I put you through."

"... Dad?"

He blinked, and suddenly clear as day, he stood in front of him.

"Oh god."

He ran towards him.

The man kneeled as Sans landed into his arms. His embrace was warm and welcoming. Sans gripped his lab coat, afraid he would disappear if he let go.

"I'm sorry, Sans." His reassuring voice echoed.

"... It's cool, dude." His voice cracked as he squeezed him harder, tears pricking in the corners of his eyes.

"Sans?"

"... Yeah?"

"You won't forget me, will you?"

Sans froze, trying to process what he just said. He slowly lifted his head up to look at him.

"... What?"

The man suddenly evaporated Sans's arms.

He remained frozen in place, his arms still outstretched. It took him a few seconds to look down at himself.

The hysteria slowly rose through him until he was screaming at the sight of the dust covering him.

* * *

Sans flung upwards in his bed, blue smoke swirling around his head as he panted. He quickly looked down at his arms. There wasn't a speck of dust.

"SANS! YOU'RE AWAKE!" he heard Papyrus shout from the other room.

Sans jumped at his voice, clutching his chest as his soul pounded. Papyrus flung into the room, joy radiating from his face. When he took a closer look at Sans, his happiness slowly faded away.

"...SANS? WHAT'S WRONG?"

He gulped and took a deep breath, taking in his surroundings.

He was back in his own room, the sun was shining through his window. It was mid day.

"... How long was I out?" He asked, forcing his breathing to calm down.

"AROUND THIRTY SIX HOURS." Papyrus said. "I'VE… I'VE BEEN WAITING FOR YOU TO WAKE UP FOR A WHILE NOW."

Sans blinked a couple of times before he moved aside his blanket and placed his feet on the floor.

"ARE YOU FEELING ANY BETTER?" He asked, watching him anxiously.

"... Where's my coat?" Sans asked, staring at the wall.

"IT'S... OVER HERE." Papyrus said as he made his way to his nightstand, where his coat was draped over the top.

"... SANS, WHY DO YOU FEEL THAT YOU NEED IT SO MUCH?" He asked as he picked it up and handed it to him.

He didn't respond. He reached his hand inside the pocket. He hit paper. He closed his eyes and took a deep breath.

"... I gotta go do somethin' real quick." He slurred, hoisting himself off of his bed.

He fumbled a little bit when he stood up. Being asleep for so long really fucks up your legs.

"I'm fine." He intruded upon seeing Papyrus raise a hand at him.

Once he regained his balance, he shrugged on his coat and began to drag his way out the door.

"SANS, WHERE ARE YOU GOING?" Papyrus called after him.

"To the lab." He mumbled, already halfway down the stairs.

"... ALRIGHT. PLEASE BE CAREFUL."

 **Author's Note: sheesh. It's been over a month, hasn't it? I'm ashamed of myself imsosorry**


End file.
